例如:如果添加5天,则add(Date.DAY,t);
添加2个月,add(Date.MONTH,2);
添加1年,add(Date.YEAR,1);
下面是ExtJs API中对Date的描述:
// Basic usage:
var dt = new Date('10/29/2006').add(Date.DAY, 5);
document.write(dt); //returns 'Fri Nov 03 2006 00:00:00'
// Negative values will be subtracted:
var dt2 = new Date('10/1/2006').add(Date.DAY, -5);
document.write(dt2); //returns 'Tue Sep 26 2006 00:00:00'
// You can even chain several calls together in one line:
var dt3 = new Date('10/1/2006').add(Date.DAY, 5).add(Date.HOUR, 8).add(Date.MINUTE, -30);
document.write(dt3); //returns 'Fri Oct 06 2006 07:30:00'
*
* @param {String} interval A valid date interval enum value.
* @param {Number} value The amount to add to the current date.
* @return {Date} The new Date instance.
*/
add : function(interval, value) {
var d = this.clone();
if (!interval || value === 0) return d;
switch(interval.toLowerCase()) {
case Date.MILLI:
d.setMilliseconds(this.getMilliseconds() + value);
break;
case Date.SECOND:
d.setSeconds(this.getSeconds() + value);
break;
case Date.MINUTE:
d.setMinutes(this.getMinutes() + value);
break;
case Date.HOUR:
d.setHours(this.getHours() + value);
break;
case Date.DAY:
d.setDate(this.getDate() + value);
break;
case Date.MONTH:
var day = this.getDate();
if (day > 28) {
day = Math.min(day, this.getFirstDateOfMonth().add('mo', value).getLastDateOfMonth().getDate());
}
d.setDate(day);
d.setMonth(this.getMonth() + value);
break;
case Date.YEAR:
d.setFullYear(this.getFullYear() + value);
break;
}
return d;
},